Authentication and identification of Chinese plant materials Periploca sepium Bunge, Acanthopanax gracilistylus W. W. Smith and Acanthopanax senticosus (Rupr. & Maxim.) Harms.

The increasing number of plant species used in herbal medicinal products leads to misidentification, incorrect plant substitutions and adulterations. Nevertheless authenticated raw material is the basic starting point for the development of a botanical product. One example is the challenging differentiation between Periplocae Cortex (Periploca sepium Bunge, family Asclepiadaceae), Acanthopanacis Cortex (Acanthopanax gracilistylus W. W. Smith, family Araliaceae) and Acanthopanacis senticosi Radix et Caulis (Acanthopanax senticosus (Rupr. & Maxim.) Harms. or Eleutherococcus senticosus Rupr. & Maxim.) Maxim., family Araliaceae). In fact, some Acanthopanacis Cortex plant material used in herbal products has been identified as its common substitute Periplocae Cortex. This is possibly due to confusion because of the Chinese names of the plants: „Ciwujia“ refers to Acanthopanacis senticosi Radix et Caulis and „Wujiapi“ to Acanthopanacis Cortex. The pinyin name of Periplocae Cortex is „Xiangjiapi“ or northern „Wujiapi“ to be distinguishable from southern „Wujiapi“ (Acanthopanacis Cortex). Nevertheless 80 percent of Acanthopanacis Cortex in the Chinese domestic market is estimated to be Periplocae Cortex [1,2]. For the bioassay-guided fractionation of anti-cancer activities of both plants authentication of plant material and plant extracts from different origin was conducted by microscopic and chromatographic methods such as TLC, GC and HPLC. The odour compounds 2-hydroxy-4-methoxybenzaldehyde, vanillin, borneol, thymol and linalool and the eleutherosides E, B and E1 were used as chemical markers. As the results were not distinct enough, they were ensured by DNA sequence analysis of the nuclear ribosomal internal transcribed spacer (ITS) of the raw materials. ITS sequence analysis finally allowed a clear discrimination of the two genera Periploca and Acanthopanax [3].

References: 1. Bensky, D., Clavey, S., Stöger, E. (2004) Chinese Herbal Medicine – Materia Medica. 3rd edition. Eastland press Inc. Seattle, USA.

2. Chinese Pharmacopoeia Commission (2005) Pharmacopoeia of the People's Republic of China. Volume I. English version. People's Medical Publishing House. Beijing, China.

3. Maruyama, T., et al. (2008) Authentication of the Traditional Medicinal Plant Eleutherococcus senticosus by DNA and Chemical Analyses. Planta Medica 74. 787–789.